Configuring Tor non-exit relay

I'm for privacy. I'm for cryptography. I do provide
Tor relays for the good of all people.
Here's how to configure a classic non-exit Tor relay on your machine. In
my case I got it running on the VPS server, with 2 IP addresses and some
bandwidth quota applied. I wanted the Tor traffic to be easily
recognizable from outside as different from the 'normal' traffic coming
from my server. Second requirement was to make Tor not use my whole
traffic quota up. Here's my config, with some notes